This invention relates to a deep banding knife of the type which includes a knife element including means for mounting the knife element on a shank of an agricultural frame so that the knife element is carried with a plurality of other knife elements across the ground for forming furrows therein. Each of the knife elements has a leading edge facing forwardly of a direction of travel which is substantially vertical for cutting the furrow in the ground. Each knife element includes at least one material supply duct mounted on the knife element rearwardly thereof relative to the leading edge so as to deposit said material into the furrow as the knife element is moved forwardly in the ground.
Deep banding has become increasingly popular in recent years as farmers attempt to reduce the cultivation which is carried out on the land for purposes of improved soil conservation.
The deep banding knife is relatively narrow so that it forms a narrow furrow in the ground and carries behind the knife firstly a supply duct for fertilizer which projects to a position just behind the knife and just above the lowermost edge of the knife so that the fertilizer is deposited substantially at the base of the furrow. In many cases the fertilizer supply duct is a seed supply duct which is positioned a little further back and a little higher so that the seed falls into the furrow on top of some soil as it begins to fall back into the furrow thus spacing the seed a little above the deep banded fertilizer.
This arrangement is relatively satisfactory and is widely used in a seeding action particularly using air distribution devices for transmitting the materials from a central supply container on the agricultural frame to each of the deep banding knives.
However as the farmer attempts to reduce the amount of cultivation of the land, the deep banding knife becomes less satisfactory in that it tends to leave weeds between the separate furrows of the knife so that the weeds can flourish and compete with the crop.
A technique is of course well known using a sweep in place of the knife but in this case the deep banding effect is reduced in view of the relatively wide furrow that is formed and the inability of the sweep to reach the depths that is desirable by the deep banding knife.
Some attempts have been made to integrate the effect of the sweep with that of the deep banding knife by attaching to the sides of the deep banding knife fins in the form of the fins of a sweep which project outwardly to the sides and then rearwardly from the knife in the conventional sweep shape. However these devices have been found to be entirely unsatisfactory in that they do not remain attached and that they are relatively weak and prone to damage and in that their effectiveness is limited.